4. Press and hold these 3 keys; Green dial key, * (star key) and no. 3 key and then press the power on/off to switch on the phone.Remember, do not let go all of the keys, hold until you see a formatting word screen show!5. After a few minutes when the full phone formatting completed, your phone will be back to original system and factory setttings.All applications installed will be lost unless you've made a backup on your mmc. You can restore the backup to the C drive again.